There are a number of different surgical procedures in which chip-sized bone is used as filler adjacent other sections of bone. For example, in a spinal fusion procedure, it is a known practice to place a compound formed out of milled bone around the rods used to hold adjacent vertebra in alignment. This compound serves as a lattice upon which the tissues forming the vertebra grow so as to form a foundation of bone around the rods. This foundation distributes the load imposed on the rods. Bone chips are also used as filler and/or growth formation lattice in orthopedic surgical procedures and other procedures such as maxillofacial procedures.
Bone chips are used as a filler/growth formation lattice in these procedures because the material, the proteins from which the bone is formed, serves as make-up material from which the blast cells of the adjacent living bone cells form new bone.
The ideal source of stock for bone chips is the patient into which the bone chips are to be packed. This is because the patient's own bone, own tissue, is less likely to be rejected by the patient's immune system than donor bone. Accordingly, in a procedure in which bone chips are required, the bone stock often harvested from one of the patient's bones afford to lose a small section of bone, typically between 0.25 and 3 cm3. Bone that is removed from the patient for transplant into another part of the patient is referred to as autograft bone.
Once the bone is harvested, it is cleaned. After cleaning, the bone is milled to form chips. The Applicant's Assignee's U.S. Patent Pub. No. US 2009/011735 A1/PCT Pub. No. WO 2009/061728 A1, BONE MILL INCLUDING A BASE AND A MILL HEAD SEPARATE FROM THE BASE, THE MILL HEAD INCLUDING A REMOVABLE CATCH TRAY, the contents of which are explicitly incorporated herein by reference, discloses a bone mill capable of converting bone stock into bone chips. This bone mill includes a base with a motor. A mill head, that contains the bone milling components, is removably attached to the base. When the head is attached to the base, the motor engages at least one of the milling components. Actuation of the motor results in a like actuation of the milling component. This results of conversion of bone stock into bone chips.
The bone mill of the incorporated by reference publication is understood to perform a more than adequate job of milling bone stock into bone chips. Nevertheless, prior to this process, it is still necessary to clean the bone to remove ligaments and other tissue that are not suitable stock for forming bone chips. Presently, surgical personnel perform this task manually using curettes, rongeurs, brushes and/or cobbs. It may take 15 minutes or more for surgical personnel to perform this process.
Moreover, to perform the cleaning process, the surgical personnel may need to firmly grasp the bone. Exerting such force on the bone may cause tearing of the gloves worn by the surgical personnel. Such tearing could result in the possibility that skin of the surgical personnel may come into direct contact with the bone. This contact can result in contamination of the bone.